/* Read ELF (Executable and Linking Format) object files for GDB.
- Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 1991-2012 Free Software Foundation, Inc.
Written by Fred Fish at Cygnus Support.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "bfd.h"
#include "gdb_string.h"
#include "elf-bfd.h"
+#include "elf/common.h"
+#include "elf/internal.h"
#include "elf/mips.h"
#include "symtab.h"
#include "symfile.h"
#include "gdb-stabs.h"
#include "complaints.h"
#include "demangle.h"
+#include "psympriv.h"
+#include "filenames.h"
+#include "probe.h"
+#include "arch-utils.h"
+#include "gdbtypes.h"
+#include "value.h"
+#include "infcall.h"
+#include "gdbthread.h"
+#include "regcache.h"
+#include "bcache.h"
extern void _initialize_elfread (void);
+/* Forward declarations. */
+static const struct sym_fns elf_sym_fns_gdb_index;
+static const struct sym_fns elf_sym_fns_lazy_psyms;
+
/* The struct elfinfo is available only during ELF symbol table and
psymtab reading. It is destroyed at the completion of psymtab-reading.
It's local to elf_symfile_read. */
struct elfinfo
{
- file_ptr dboffset; /* Offset to dwarf debug section */
- unsigned int dbsize; /* Size of dwarf debug section */
- file_ptr lnoffset; /* Offset to dwarf line number section */
- unsigned int lnsize; /* Size of dwarf line number section */
asection *stabsect; /* Section pointer for .stab section */
asection *stabindexsect; /* Section pointer for .stab.index section */
asection *mdebugsect; /* Section pointer for .mdebug section */
};
+/* Per-objfile data for probe info. */
+
+static const struct objfile_data *probe_key = NULL;
+
static void free_elfinfo (void *);
+/* Minimal symbols located at the GOT entries for .plt - that is the real
+ pointer where the given entry will jump to. It gets updated by the real
+ function address during lazy ld.so resolving in the inferior. These
+ minimal symbols are indexed for <tab>-completion. */
+
+#define SYMBOL_GOT_PLT_SUFFIX "@got.plt"
+
+/* Locate the segments in ABFD. */
+
+static struct symfile_segment_data *
+elf_symfile_segments (bfd *abfd)
+{
+ Elf_Internal_Phdr *phdrs, **segments;
+ long phdrs_size;
+ int num_phdrs, num_segments, num_sections, i;
+ asection *sect;
+ struct symfile_segment_data *data;
+
+ phdrs_size = bfd_get_elf_phdr_upper_bound (abfd);
+ if (phdrs_size == -1)
+ return NULL;
+
+ phdrs = alloca (phdrs_size);
+ num_phdrs = bfd_get_elf_phdrs (abfd, phdrs);
+ if (num_phdrs == -1)
+ return NULL;
+
+ num_segments = 0;
+ segments = alloca (sizeof (Elf_Internal_Phdr *) * num_phdrs);
+ for (i = 0; i < num_phdrs; i++)
+ if (phdrs[i].p_type == PT_LOAD)
+ segments[num_segments++] = &phdrs[i];
+
+ if (num_segments == 0)
+ return NULL;
+
+ data = XZALLOC (struct symfile_segment_data);
+ data->num_segments = num_segments;
+ data->segment_bases = XCALLOC (num_segments, CORE_ADDR);
+ data->segment_sizes = XCALLOC (num_segments, CORE_ADDR);
+
+ for (i = 0; i < num_segments; i++)
+ {
+ data->segment_bases[i] = segments[i]->p_vaddr;
+ data->segment_sizes[i] = segments[i]->p_memsz;
+ }
+
+ num_sections = bfd_count_sections (abfd);
+ data->segment_info = XCALLOC (num_sections, int);
+
+ for (i = 0, sect = abfd->sections; sect != NULL; i++, sect = sect->next)
+ {
+ int j;
+ CORE_ADDR vma;
+
+ if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
+ continue;
+
+ vma = bfd_get_section_vma (abfd, sect);
+
+ for (j = 0; j < num_segments; j++)
+ if (segments[j]->p_memsz > 0
+ && vma >= segments[j]->p_vaddr
+ && (vma - segments[j]->p_vaddr) < segments[j]->p_memsz)
+ {
+ data->segment_info[i] = j + 1;
+ break;
+ }
+
+ /* We should have found a segment for every non-empty section.
+ If we haven't, we will not relocate this section by any
+ offsets we apply to the segments. As an exception, do not
+ warn about SHT_NOBITS sections; in normal ELF execution
+ environments, SHT_NOBITS means zero-initialized and belongs
+ in a segment, but in no-OS environments some tools (e.g. ARM
+ RealView) use SHT_NOBITS for uninitialized data. Since it is
+ uninitialized, it doesn't need a program header. Such
+ binaries are not relocatable. */
+ if (bfd_get_section_size (sect) > 0 && j == num_segments
+ && (bfd_get_section_flags (abfd, sect) & SEC_LOAD) != 0)
+ warning (_("Loadable section \"%s\" outside of ELF segments"),
+ bfd_section_name (abfd, sect));
+ }
+
+ return data;
+}
+
/* We are called once per section from elf_symfile_read. We
need to examine each section we are passed, check to see
if it is something we are interested in processing, and
FIXME: The section names should not be hardwired strings (what
should they be? I don't think most object file formats have enough
- section flags to specify what kind of debug section it is
+ section flags to specify what kind of debug section it is.
-kingdon). */
static void
struct elfinfo *ei;
ei = (struct elfinfo *) eip;
- if (strcmp (sectp->name, ".debug") == 0)
- {
- ei->dboffset = sectp->filepos;
- ei->dbsize = bfd_get_section_size (sectp);
- }
- else if (strcmp (sectp->name, ".line") == 0)
- {
- ei->lnoffset = sectp->filepos;
- ei->lnsize = bfd_get_section_size (sectp);
- }
- else if (strcmp (sectp->name, ".stab") == 0)
+ if (strcmp (sectp->name, ".stab") == 0)
{
ei->stabsect = sectp;
}
}
static struct minimal_symbol *
-record_minimal_symbol (char *name, CORE_ADDR address,
+record_minimal_symbol (const char *name, int name_len, int copy_name,
+ CORE_ADDR address,
enum minimal_symbol_type ms_type,
asection *bfd_section, struct objfile *objfile)
{
- if (ms_type == mst_text || ms_type == mst_file_text)
- address = SMASH_TEXT_ADDRESS (address);
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
- return prim_record_minimal_symbol_and_info
- (name, address, ms_type, NULL, bfd_section->index, bfd_section, objfile);
-}
-
-/*
-
- LOCAL FUNCTION
+ if (ms_type == mst_text || ms_type == mst_file_text
+ || ms_type == mst_text_gnu_ifunc)
+ address = gdbarch_smash_text_address (gdbarch, address);
- elf_symtab_read -- read the symbol table of an ELF file
-
- SYNOPSIS
-
- void elf_symtab_read (struct objfile *objfile, int dynamic)
+ return prim_record_minimal_symbol_full (name, name_len, copy_name, address,
+ ms_type, bfd_section->index,
+ bfd_section, objfile);
+}
- DESCRIPTION
+/* Read the symbol table of an ELF file.
- Given an objfile and a flag that specifies whether or not the objfile
- is for an executable or not (may be shared library for example), add
- all the global function and data symbols to the minimal symbol table.
+ Given an objfile, a symbol table, and a flag indicating whether the
+ symbol table contains regular, dynamic, or synthetic symbols, add all
+ the global function and data symbols to the minimal symbol table.
In stabs-in-ELF, as implemented by Sun, there are some local symbols
defined in the ELF symbol table, which can be used to locate
the beginnings of sections from each ".o" file that was linked to
form the executable objfile. We gather any such info and record it
- in data structures hung off the objfile's private data.
+ in data structures hung off the objfile's private data. */
- */
+#define ST_REGULAR 0
+#define ST_DYNAMIC 1
+#define ST_SYNTHETIC 2
static void
-elf_symtab_read (struct objfile *objfile, int dynamic)
+elf_symtab_read (struct objfile *objfile, int type,
+ long number_of_symbols, asymbol **symbol_table,
+ int copy_names)
{
- long storage_needed;
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
asymbol *sym;
- asymbol **symbol_table;
- long number_of_symbols;
long i;
- struct cleanup *back_to;
CORE_ADDR symaddr;
CORE_ADDR offset;
enum minimal_symbol_type ms_type;
/* If filesym is nonzero, it points to a file symbol, but we haven't
seen any section info for it yet. */
asymbol *filesym = 0;
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- /* Name of filesym, as saved on the objfile_obstack. */
- char *filesymname = obsavestring ("", 0, &objfile->objfile_obstack);
-#endif
- struct dbx_symfile_info *dbx = objfile->sym_stab_info;
+ /* Name of filesym. This is either a constant string or is saved on
+ the objfile's filename cache. */
+ const char *filesymname = "";
+ struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info;
int stripped = (bfd_get_symcount (objfile->obfd) == 0);
- if (dynamic)
+ for (i = 0; i < number_of_symbols; i++)
{
- storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd);
+ sym = symbol_table[i];
+ if (sym->name == NULL || *sym->name == '\0')
+ {
+ /* Skip names that don't exist (shouldn't happen), or names
+ that are null strings (may happen). */
+ continue;
+ }
- /* Nothing to be done if there is no dynamic symtab. */
- if (storage_needed < 0)
- return;
- }
- else
- {
- storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
- if (storage_needed < 0)
- error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd),
- bfd_errmsg (bfd_get_error ()));
- }
- if (storage_needed > 0)
- {
- symbol_table = (asymbol **) xmalloc (storage_needed);
- back_to = make_cleanup (xfree, symbol_table);
- if (dynamic)
- number_of_symbols = bfd_canonicalize_dynamic_symtab (objfile->obfd,
- symbol_table);
- else
- number_of_symbols = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
- if (number_of_symbols < 0)
- error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd),
- bfd_errmsg (bfd_get_error ()));
+ /* Skip "special" symbols, e.g. ARM mapping symbols. These are
+ symbols which do not correspond to objects in the symbol table,
+ but have some other target-specific meaning. */
+ if (bfd_is_target_special_symbol (objfile->obfd, sym))
+ {
+ if (gdbarch_record_special_symbol_p (gdbarch))
+ gdbarch_record_special_symbol (gdbarch, objfile, sym);
+ continue;
+ }
- for (i = 0; i < number_of_symbols; i++)
+ offset = ANOFFSET (objfile->section_offsets, sym->section->index);
+ if (type == ST_DYNAMIC
+ && sym->section == &bfd_und_section
+ && (sym->flags & BSF_FUNCTION))
{
- sym = symbol_table[i];
- if (sym->name == NULL || *sym->name == '\0')
- {
- /* Skip names that don't exist (shouldn't happen), or names
- that are null strings (may happen). */
- continue;
- }
+ struct minimal_symbol *msym;
+ bfd *abfd = objfile->obfd;
+ asection *sect;
+
+ /* Symbol is a reference to a function defined in
+ a shared library.
+ If its value is non zero then it is usually the address
+ of the corresponding entry in the procedure linkage table,
+ plus the desired section offset.
+ If its value is zero then the dynamic linker has to resolve
+ the symbol. We are unable to find any meaningful address
+ for this symbol in the executable file, so we skip it. */
+ symaddr = sym->value;
+ if (symaddr == 0)
+ continue;
- offset = ANOFFSET (objfile->section_offsets, sym->section->index);
- if (dynamic
- && sym->section == &bfd_und_section
- && (sym->flags & BSF_FUNCTION))
+ /* sym->section is the undefined section. However, we want to
+ record the section where the PLT stub resides with the
+ minimal symbol. Search the section table for the one that
+ covers the stub's address. */
+ for (sect = abfd->sections; sect != NULL; sect = sect->next)
{
- struct minimal_symbol *msym;
-
- /* Symbol is a reference to a function defined in
- a shared library.
- If its value is non zero then it is usually the address
- of the corresponding entry in the procedure linkage table,
- plus the desired section offset.
- If its value is zero then the dynamic linker has to resolve
- the symbol. We are unable to find any meaningful address
- for this symbol in the executable file, so we skip it. */
- symaddr = sym->value;
- if (symaddr == 0)
+ if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
continue;
- symaddr += offset;
- msym = record_minimal_symbol
- ((char *) sym->name, symaddr,
- mst_solib_trampoline, sym->section, objfile);
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (msym != NULL)
- msym->filename = filesymname;
-#endif
- continue;
+
+ if (symaddr >= bfd_get_section_vma (abfd, sect)
+ && symaddr < bfd_get_section_vma (abfd, sect)
+ + bfd_get_section_size (sect))
+ break;
}
+ if (!sect)
+ continue;
- /* If it is a nonstripped executable, do not enter dynamic
- symbols, as the dynamic symbol table is usually a subset
- of the main symbol table. */
- if (dynamic && !stripped)
+ /* On ia64-hpux, we have discovered that the system linker
+ adds undefined symbols with nonzero addresses that cannot
+ be right (their address points inside the code of another
+ function in the .text section). This creates problems
+ when trying to determine which symbol corresponds to
+ a given address.
+
+ We try to detect those buggy symbols by checking which
+ section we think they correspond to. Normally, PLT symbols
+ are stored inside their own section, and the typical name
+ for that section is ".plt". So, if there is a ".plt"
+ section, and yet the section name of our symbol does not
+ start with ".plt", we ignore that symbol. */
+ if (strncmp (sect->name, ".plt", 4) != 0
+ && bfd_get_section_by_name (abfd, ".plt") != NULL)
continue;
- if (sym->flags & BSF_FILE)
+
+ symaddr += ANOFFSET (objfile->section_offsets, sect->index);
+
+ msym = record_minimal_symbol
+ (sym->name, strlen (sym->name), copy_names,
+ symaddr, mst_solib_trampoline, sect, objfile);
+ if (msym != NULL)
+ msym->filename = filesymname;
+ continue;
+ }
+
+ /* If it is a nonstripped executable, do not enter dynamic
+ symbols, as the dynamic symbol table is usually a subset
+ of the main symbol table. */
+ if (type == ST_DYNAMIC && !stripped)
+ continue;
+ if (sym->flags & BSF_FILE)
+ {
+ /* STT_FILE debugging symbol that helps stabs-in-elf debugging.
+ Chain any old one onto the objfile; remember new sym. */
+ if (sectinfo != NULL)
+ {
+ sectinfo->next = dbx->stab_section_info;
+ dbx->stab_section_info = sectinfo;
+ sectinfo = NULL;
+ }
+ filesym = sym;
+ filesymname = bcache (filesym->name, strlen (filesym->name) + 1,
+ objfile->filename_cache);
+ }
+ else if (sym->flags & BSF_SECTION_SYM)
+ continue;
+ else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
+ {
+ struct minimal_symbol *msym;
+
+ /* Select global/local/weak symbols. Note that bfd puts abs
+ symbols in their own section, so all symbols we are
+ interested in will have a section. */
+ /* Bfd symbols are section relative. */
+ symaddr = sym->value + sym->section->vma;
+ /* Relocate all non-absolute and non-TLS symbols by the
+ section offset. */
+ if (sym->section != &bfd_abs_section
+ && !(sym->section->flags & SEC_THREAD_LOCAL))
{
- /* STT_FILE debugging symbol that helps stabs-in-elf debugging.
- Chain any old one onto the objfile; remember new sym. */
- if (sectinfo != NULL)
+ symaddr += offset;
+ }
+ /* For non-absolute symbols, use the type of the section
+ they are relative to, to intuit text/data. Bfd provides
+ no way of figuring this out for absolute symbols. */
+ if (sym->section == &bfd_abs_section)
+ {
+ /* This is a hack to get the minimal symbol type
+ right for Irix 5, which has absolute addresses
+ with special section indices for dynamic symbols.
+
+ NOTE: uweigand-20071112: Synthetic symbols do not
+ have an ELF-private part, so do not touch those. */
+ unsigned int shndx = type == ST_SYNTHETIC ? 0 :
+ ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
+
+ switch (shndx)
+ {
+ case SHN_MIPS_TEXT:
+ ms_type = mst_text;
+ break;
+ case SHN_MIPS_DATA:
+ ms_type = mst_data;
+ break;
+ case SHN_MIPS_ACOMMON:
+ ms_type = mst_bss;
+ break;
+ default:
+ ms_type = mst_abs;
+ }
+
+ /* If it is an Irix dynamic symbol, skip section name
+ symbols, relocate all others by section offset. */
+ if (ms_type != mst_abs)
{
- sectinfo->next = dbx->stab_section_info;
- dbx->stab_section_info = sectinfo;
- sectinfo = NULL;
+ if (sym->name[0] == '.')
+ continue;
+ symaddr += offset;
}
- filesym = sym;
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- filesymname =
- obsavestring ((char *) filesym->name, strlen (filesym->name),
- &objfile->objfile_obstack);
-#endif
}
- else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
+ else if (sym->section->flags & SEC_CODE)
{
- struct minimal_symbol *msym;
-
- /* Select global/local/weak symbols. Note that bfd puts abs
- symbols in their own section, so all symbols we are
- interested in will have a section. */
- /* Bfd symbols are section relative. */
- symaddr = sym->value + sym->section->vma;
- /* Relocate all non-absolute symbols by the section offset. */
- if (sym->section != &bfd_abs_section)
+ if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
{
- symaddr += offset;
+ if (sym->flags & BSF_GNU_INDIRECT_FUNCTION)
+ ms_type = mst_text_gnu_ifunc;
+ else
+ ms_type = mst_text;
}
- /* For non-absolute symbols, use the type of the section
- they are relative to, to intuit text/data. Bfd provides
- no way of figuring this out for absolute symbols. */
- if (sym->section == &bfd_abs_section)
+ /* The BSF_SYNTHETIC check is there to omit ppc64 function
+ descriptors mistaken for static functions starting with 'L'.
+ */
+ else if ((sym->name[0] == '.' && sym->name[1] == 'L'
+ && (sym->flags & BSF_SYNTHETIC) == 0)
+ || ((sym->flags & BSF_LOCAL)
+ && sym->name[0] == '$'
+ && sym->name[1] == 'L'))
+ /* Looks like a compiler-generated label. Skip
+ it. The assembler should be skipping these (to
+ keep executables small), but apparently with
+ gcc on the (deleted) delta m88k SVR4, it loses.
+ So to have us check too should be harmless (but
+ I encourage people to fix this in the assembler
+ instead of adding checks here). */
+ continue;
+ else
{
- /* This is a hack to get the minimal symbol type
- right for Irix 5, which has absolute addresses
- with special section indices for dynamic symbols. */
- unsigned short shndx =
- ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
-
- switch (shndx)
- {
- case SHN_MIPS_TEXT:
- ms_type = mst_text;
- break;
- case SHN_MIPS_DATA:
- ms_type = mst_data;
- break;
- case SHN_MIPS_ACOMMON:
- ms_type = mst_bss;
- break;
- default:
- ms_type = mst_abs;
- }
-
- /* If it is an Irix dynamic symbol, skip section name
- symbols, relocate all others by section offset. */
- if (ms_type != mst_abs)
- {
- if (sym->name[0] == '.')
- continue;
- symaddr += offset;
- }
+ ms_type = mst_file_text;
}
- else if (sym->section->flags & SEC_CODE)
+ }
+ else if (sym->section->flags & SEC_ALLOC)
+ {
+ if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
{
- if (sym->flags & BSF_GLOBAL)
+ if (sym->section->flags & SEC_LOAD)
{
- ms_type = mst_text;
+ ms_type = mst_data;
}
- else if ((sym->name[0] == '.' && sym->name[1] == 'L')
- || ((sym->flags & BSF_LOCAL)
- && sym->name[0] == '$'
- && sym->name[1] == 'L'))
- /* Looks like a compiler-generated label. Skip
- it. The assembler should be skipping these (to
- keep executables small), but apparently with
- gcc on the (deleted) delta m88k SVR4, it loses.
- So to have us check too should be harmless (but
- I encourage people to fix this in the assembler
- instead of adding checks here). */
- continue;
else
{
- ms_type = mst_file_text;
+ ms_type = mst_bss;
}
}
- else if (sym->section->flags & SEC_ALLOC)
+ else if (sym->flags & BSF_LOCAL)
{
- if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
- {
- if (sym->section->flags & SEC_LOAD)
- {
- ms_type = mst_data;
- }
- else
- {
- ms_type = mst_bss;
- }
- }
- else if (sym->flags & BSF_LOCAL)
+ /* Named Local variable in a Data section.
+ Check its name for stabs-in-elf. */
+ int special_local_sect;
+
+ if (strcmp ("Bbss.bss", sym->name) == 0)
+ special_local_sect = SECT_OFF_BSS (objfile);
+ else if (strcmp ("Ddata.data", sym->name) == 0)
+ special_local_sect = SECT_OFF_DATA (objfile);
+ else if (strcmp ("Drodata.rodata", sym->name) == 0)
+ special_local_sect = SECT_OFF_RODATA (objfile);
+ else
+ special_local_sect = -1;
+ if (special_local_sect >= 0)
{
- /* Named Local variable in a Data section.
- Check its name for stabs-in-elf. */
- int special_local_sect;
- if (strcmp ("Bbss.bss", sym->name) == 0)
- special_local_sect = SECT_OFF_BSS (objfile);
- else if (strcmp ("Ddata.data", sym->name) == 0)
- special_local_sect = SECT_OFF_DATA (objfile);
- else if (strcmp ("Drodata.rodata", sym->name) == 0)
- special_local_sect = SECT_OFF_RODATA (objfile);
- else
- special_local_sect = -1;
- if (special_local_sect >= 0)
+ /* Found a special local symbol. Allocate a
+ sectinfo, if needed, and fill it in. */
+ if (sectinfo == NULL)
{
- /* Found a special local symbol. Allocate a
- sectinfo, if needed, and fill it in. */
- if (sectinfo == NULL)
+ int max_index;
+ size_t size;
+
+ max_index = SECT_OFF_BSS (objfile);
+ if (objfile->sect_index_data > max_index)
+ max_index = objfile->sect_index_data;
+ if (objfile->sect_index_rodata > max_index)
+ max_index = objfile->sect_index_rodata;
+
+ /* max_index is the largest index we'll
+ use into this array, so we must
+ allocate max_index+1 elements for it.
+ However, 'struct stab_section_info'
+ already includes one element, so we
+ need to allocate max_index aadditional
+ elements. */
+ size = (sizeof (struct stab_section_info)
+ + (sizeof (CORE_ADDR) * max_index));
+ sectinfo = (struct stab_section_info *)
+ xmalloc (size);
+ memset (sectinfo, 0, size);
+ sectinfo->num_sections = max_index;
+ if (filesym == NULL)
{
- int max_index;
- size_t size;
-
- max_index
- = max (SECT_OFF_BSS (objfile),
- max (SECT_OFF_DATA (objfile),
- SECT_OFF_RODATA (objfile)));
-
- /* max_index is the largest index we'll
- use into this array, so we must
- allocate max_index+1 elements for it.
- However, 'struct stab_section_info'
- already includes one element, so we
- need to allocate max_index aadditional
- elements. */
- size = (sizeof (struct stab_section_info)
- + (sizeof (CORE_ADDR)
- * max_index));
- sectinfo = (struct stab_section_info *)
- xmalloc (size);
- memset (sectinfo, 0, size);
- sectinfo->num_sections = max_index;
- if (filesym == NULL)
- {
- complaint (&symfile_complaints,
- "elf/stab section information %s without a preceding file symbol",
- sym->name);
- }
- else
- {
- sectinfo->filename =
- (char *) filesym->name;
- }
+ complaint (&symfile_complaints,
+ _("elf/stab section information %s "
+ "without a preceding file symbol"),
+ sym->name);
+ }
+ else
+ {
+ sectinfo->filename =
+ (char *) filesym->name;
}
- if (sectinfo->sections[special_local_sect] != 0)
- complaint (&symfile_complaints,
- "duplicated elf/stab section information for %s",
- sectinfo->filename);
- /* BFD symbols are section relative. */
- symaddr = sym->value + sym->section->vma;
- /* Relocate non-absolute symbols by the
- section offset. */
- if (sym->section != &bfd_abs_section)
- symaddr += offset;
- sectinfo->sections[special_local_sect] = symaddr;
- /* The special local symbols don't go in the
- minimal symbol table, so ignore this one. */
- continue;
- }
- /* Not a special stabs-in-elf symbol, do regular
- symbol processing. */
- if (sym->section->flags & SEC_LOAD)
- {
- ms_type = mst_file_data;
- }
- else
- {
- ms_type = mst_file_bss;
}
+ if (sectinfo->sections[special_local_sect] != 0)
+ complaint (&symfile_complaints,
+ _("duplicated elf/stab section "
+ "information for %s"),
+ sectinfo->filename);
+ /* BFD symbols are section relative. */
+ symaddr = sym->value + sym->section->vma;
+ /* Relocate non-absolute symbols by the
+ section offset. */
+ if (sym->section != &bfd_abs_section)
+ symaddr += offset;
+ sectinfo->sections[special_local_sect] = symaddr;
+ /* The special local symbols don't go in the
+ minimal symbol table, so ignore this one. */
+ continue;
+ }
+ /* Not a special stabs-in-elf symbol, do regular
+ symbol processing. */
+ if (sym->section->flags & SEC_LOAD)
+ {
+ ms_type = mst_file_data;
}
else
{
- ms_type = mst_unknown;
+ ms_type = mst_file_bss;
}
}
else
{
- /* FIXME: Solaris2 shared libraries include lots of
- odd "absolute" and "undefined" symbols, that play
- hob with actions like finding what function the PC
- is in. Ignore them if they aren't text, data, or bss. */
- /* ms_type = mst_unknown; */
- continue; /* Skip this symbol. */
+ ms_type = mst_unknown;
+ }
+ }
+ else
+ {
+ /* FIXME: Solaris2 shared libraries include lots of
+ odd "absolute" and "undefined" symbols, that play
+ hob with actions like finding what function the PC
+ is in. Ignore them if they aren't text, data, or bss. */
+ /* ms_type = mst_unknown; */
+ continue; /* Skip this symbol. */
+ }
+ msym = record_minimal_symbol
+ (sym->name, strlen (sym->name), copy_names, symaddr,
+ ms_type, sym->section, objfile);
+
+ if (msym)
+ {
+ /* Pass symbol size field in via BFD. FIXME!!! */
+ elf_symbol_type *elf_sym;
+
+ /* NOTE: uweigand-20071112: A synthetic symbol does not have an
+ ELF-private part. However, in some cases (e.g. synthetic
+ 'dot' symbols on ppc64) the udata.p entry is set to point back
+ to the original ELF symbol it was derived from. Get the size
+ from that symbol. */
+ if (type != ST_SYNTHETIC)
+ elf_sym = (elf_symbol_type *) sym;
+ else
+ elf_sym = (elf_symbol_type *) sym->udata.p;
+
+ if (elf_sym)
+ MSYMBOL_SIZE(msym) = elf_sym->internal_elf_sym.st_size;
+
+ msym->filename = filesymname;
+ gdbarch_elf_make_msymbol_special (gdbarch, sym, msym);
+ }
+
+ /* For @plt symbols, also record a trampoline to the
+ destination symbol. The @plt symbol will be used in
+ disassembly, and the trampoline will be used when we are
+ trying to find the target. */
+ if (msym && ms_type == mst_text && type == ST_SYNTHETIC)
+ {
+ int len = strlen (sym->name);
+
+ if (len > 4 && strcmp (sym->name + len - 4, "@plt") == 0)
+ {
+ struct minimal_symbol *mtramp;
+
+ mtramp = record_minimal_symbol (sym->name, len - 4, 1,
+ symaddr,
+ mst_solib_trampoline,
+ sym->section, objfile);
+ if (mtramp)
+ {
+ MSYMBOL_SIZE (mtramp) = MSYMBOL_SIZE (msym);
+ mtramp->filename = filesymname;
+ gdbarch_elf_make_msymbol_special (gdbarch, sym, mtramp);
+ }
}
- msym = record_minimal_symbol
- ((char *) sym->name, symaddr,
- ms_type, sym->section, objfile);
- if (msym)
- {
- /* Pass symbol size field in via BFD. FIXME!!! */
- unsigned long size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size;
- MSYMBOL_SIZE(msym) = size;
- }
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (msym != NULL)
- msym->filename = filesymname;
-#endif
- ELF_MAKE_MSYMBOL_SPECIAL (sym, msym);
}
}
- do_cleanups (back_to);
}
}
+/* Build minimal symbols named `function@got.plt' (see SYMBOL_GOT_PLT_SUFFIX)
+ for later look ups of which function to call when user requests
+ a STT_GNU_IFUNC function. As the STT_GNU_IFUNC type is found at the target
+ library defining `function' we cannot yet know while reading OBJFILE which
+ of the SYMBOL_GOT_PLT_SUFFIX entries will be needed and later
+ DYN_SYMBOL_TABLE is no longer easily available for OBJFILE. */
+
+static void
+elf_rel_plt_read (struct objfile *objfile, asymbol **dyn_symbol_table)
+{
+ bfd *obfd = objfile->obfd;
+ const struct elf_backend_data *bed = get_elf_backend_data (obfd);
+ asection *plt, *relplt, *got_plt;
+ unsigned u;
+ int plt_elf_idx;
+ bfd_size_type reloc_count, reloc;
+ char *string_buffer = NULL;
+ size_t string_buffer_size = 0;
+ struct cleanup *back_to;
+ struct gdbarch *gdbarch = objfile->gdbarch;
+ struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
+ size_t ptr_size = TYPE_LENGTH (ptr_type);
+
+ if (objfile->separate_debug_objfile_backlink)
+ return;
+
+ plt = bfd_get_section_by_name (obfd, ".plt");
+ if (plt == NULL)
+ return;
+ plt_elf_idx = elf_section_data (plt)->this_idx;
+
+ got_plt = bfd_get_section_by_name (obfd, ".got.plt");
+ if (got_plt == NULL)
+ return;
+
+ /* This search algorithm is from _bfd_elf_canonicalize_dynamic_reloc. */
+ for (relplt = obfd->sections; relplt != NULL; relplt = relplt->next)
+ if (elf_section_data (relplt)->this_hdr.sh_info == plt_elf_idx
+ && (elf_section_data (relplt)->this_hdr.sh_type == SHT_REL
+ || elf_section_data (relplt)->this_hdr.sh_type == SHT_RELA))
+ break;
+ if (relplt == NULL)
+ return;
+
+ if (! bed->s->slurp_reloc_table (obfd, relplt, dyn_symbol_table, TRUE))
+ return;
+
+ back_to = make_cleanup (free_current_contents, &string_buffer);
+
+ reloc_count = relplt->size / elf_section_data (relplt)->this_hdr.sh_entsize;
+ for (reloc = 0; reloc < reloc_count; reloc++)
+ {
+ const char *name, *name_got_plt;
+ struct minimal_symbol *msym;
+ CORE_ADDR address;
+ const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
+ size_t name_len;
+
+ name = bfd_asymbol_name (*relplt->relocation[reloc].sym_ptr_ptr);
+ name_len = strlen (name);
+ address = relplt->relocation[reloc].address;
+
+ /* Does the pointer reside in the .got.plt section? */
+ if (!(bfd_get_section_vma (obfd, got_plt) <= address
+ && address < bfd_get_section_vma (obfd, got_plt)
+ + bfd_get_section_size (got_plt)))
+ continue;
+
+ /* We cannot check if NAME is a reference to mst_text_gnu_ifunc as in
+ OBJFILE the symbol is undefined and the objfile having NAME defined
+ may not yet have been loaded. */
+
+ if (string_buffer_size < name_len + got_suffix_len + 1)
+ {
+ string_buffer_size = 2 * (name_len + got_suffix_len);
+ string_buffer = xrealloc (string_buffer, string_buffer_size);
+ }
+ memcpy (string_buffer, name, name_len);
+ memcpy (&string_buffer[name_len], SYMBOL_GOT_PLT_SUFFIX,
+ got_suffix_len + 1);
+
+ msym = record_minimal_symbol (string_buffer, name_len + got_suffix_len,
+ 1, address, mst_slot_got_plt, got_plt,
+ objfile);
+ if (msym)
+ MSYMBOL_SIZE (msym) = ptr_size;
+ }
+
+ do_cleanups (back_to);
+}
+
+/* The data pointer is htab_t for gnu_ifunc_record_cache_unchecked. */
+
+static const struct objfile_data *elf_objfile_gnu_ifunc_cache_data;
+
+/* Map function names to CORE_ADDR in elf_objfile_gnu_ifunc_cache_data. */
+
+struct elf_gnu_ifunc_cache
+{
+ /* This is always a function entry address, not a function descriptor. */
+ CORE_ADDR addr;
+
+ char name[1];
+};
+
+/* htab_hash for elf_objfile_gnu_ifunc_cache_data. */
+
+static hashval_t
+elf_gnu_ifunc_cache_hash (const void *a_voidp)
+{
+ const struct elf_gnu_ifunc_cache *a = a_voidp;
+
+ return htab_hash_string (a->name);
+}
+
+/* htab_eq for elf_objfile_gnu_ifunc_cache_data. */
+
+static int
+elf_gnu_ifunc_cache_eq (const void *a_voidp, const void *b_voidp)
+{
+ const struct elf_gnu_ifunc_cache *a = a_voidp;
+ const struct elf_gnu_ifunc_cache *b = b_voidp;
+
+ return strcmp (a->name, b->name) == 0;
+}
+
+/* Record the target function address of a STT_GNU_IFUNC function NAME is the
+ function entry address ADDR. Return 1 if NAME and ADDR are considered as
+ valid and therefore they were successfully recorded, return 0 otherwise.
+
+ Function does not expect a duplicate entry. Use
+ elf_gnu_ifunc_resolve_by_cache first to check if the entry for NAME already
+ exists. */
+
+static int
+elf_gnu_ifunc_record_cache (const char *name, CORE_ADDR addr)
+{
+ struct minimal_symbol *msym;
+ asection *sect;
+ struct objfile *objfile;
+ htab_t htab;
+ struct elf_gnu_ifunc_cache entry_local, *entry_p;
+ void **slot;
+
+ msym = lookup_minimal_symbol_by_pc (addr);
+ if (msym == NULL)
+ return 0;
+ if (SYMBOL_VALUE_ADDRESS (msym) != addr)
+ return 0;
+ /* minimal symbols have always SYMBOL_OBJ_SECTION non-NULL. */
+ sect = SYMBOL_OBJ_SECTION (msym)->the_bfd_section;
+ objfile = SYMBOL_OBJ_SECTION (msym)->objfile;
+
+ /* If .plt jumps back to .plt the symbol is still deferred for later
+ resolution and it has no use for GDB. Besides ".text" this symbol can
+ reside also in ".opd" for ppc64 function descriptor. */
+ if (strcmp (bfd_get_section_name (objfile->obfd, sect), ".plt") == 0)
+ return 0;
+
+ htab = objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data);
+ if (htab == NULL)
+ {
+ htab = htab_create_alloc_ex (1, elf_gnu_ifunc_cache_hash,
+ elf_gnu_ifunc_cache_eq,
+ NULL, &objfile->objfile_obstack,
+ hashtab_obstack_allocate,
+ dummy_obstack_deallocate);
+ set_objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data, htab);
+ }
+
+ entry_local.addr = addr;
+ obstack_grow (&objfile->objfile_obstack, &entry_local,
+ offsetof (struct elf_gnu_ifunc_cache, name));
+ obstack_grow_str0 (&objfile->objfile_obstack, name);
+ entry_p = obstack_finish (&objfile->objfile_obstack);
+
+ slot = htab_find_slot (htab, entry_p, INSERT);
+ if (*slot != NULL)
+ {
+ struct elf_gnu_ifunc_cache *entry_found_p = *slot;
+ struct gdbarch *gdbarch = objfile->gdbarch;
+
+ if (entry_found_p->addr != addr)
+ {
+ /* This case indicates buggy inferior program, the resolved address
+ should never change. */
+
+ warning (_("gnu-indirect-function \"%s\" has changed its resolved "
+ "function_address from %s to %s"),
+ name, paddress (gdbarch, entry_found_p->addr),
+ paddress (gdbarch, addr));
+ }
+
+ /* New ENTRY_P is here leaked/duplicate in the OBJFILE obstack. */
+ }
+ *slot = entry_p;
+
+ return 1;
+}
+
+/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
+ function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
+ is not NULL) and the function returns 1. It returns 0 otherwise.
+
+ Only the elf_objfile_gnu_ifunc_cache_data hash table is searched by this
+ function. */
+
+static int
+elf_gnu_ifunc_resolve_by_cache (const char *name, CORE_ADDR *addr_p)
+{
+ struct objfile *objfile;
+
+ ALL_PSPACE_OBJFILES (current_program_space, objfile)
+ {
+ htab_t htab;
+ struct elf_gnu_ifunc_cache *entry_p;
+ void **slot;
+
+ htab = objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data);
+ if (htab == NULL)
+ continue;
+
+ entry_p = alloca (sizeof (*entry_p) + strlen (name));
+ strcpy (entry_p->name, name);
+
+ slot = htab_find_slot (htab, entry_p, NO_INSERT);
+ if (slot == NULL)
+ continue;
+ entry_p = *slot;
+ gdb_assert (entry_p != NULL);
+
+ if (addr_p)
+ *addr_p = entry_p->addr;
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
+ function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
+ is not NULL) and the function returns 1. It returns 0 otherwise.
+
+ Only the SYMBOL_GOT_PLT_SUFFIX locations are searched by this function.
+ elf_gnu_ifunc_resolve_by_cache must have been already called for NAME to
+ prevent cache entries duplicates. */
+
+static int
+elf_gnu_ifunc_resolve_by_got (const char *name, CORE_ADDR *addr_p)
+{
+ char *name_got_plt;
+ struct objfile *objfile;
+ const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
+
+ name_got_plt = alloca (strlen (name) + got_suffix_len + 1);
+ sprintf (name_got_plt, "%s" SYMBOL_GOT_PLT_SUFFIX, name);
+
+ ALL_PSPACE_OBJFILES (current_program_space, objfile)
+ {
+ bfd *obfd = objfile->obfd;
+ struct gdbarch *gdbarch = objfile->gdbarch;
+ struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
+ size_t ptr_size = TYPE_LENGTH (ptr_type);
+ CORE_ADDR pointer_address, addr;
+ asection *plt;
+ gdb_byte *buf = alloca (ptr_size);
+ struct minimal_symbol *msym;
+
+ msym = lookup_minimal_symbol (name_got_plt, NULL, objfile);
+ if (msym == NULL)
+ continue;
+ if (MSYMBOL_TYPE (msym) != mst_slot_got_plt)
+ continue;
+ pointer_address = SYMBOL_VALUE_ADDRESS (msym);
+
+ plt = bfd_get_section_by_name (obfd, ".plt");
+ if (plt == NULL)
+ continue;
+
+ if (MSYMBOL_SIZE (msym) != ptr_size)
+ continue;
+ if (target_read_memory (pointer_address, buf, ptr_size) != 0)
+ continue;
+ addr = extract_typed_address (buf, ptr_type);
+ addr = gdbarch_convert_from_func_ptr_addr (gdbarch, addr,
+ ¤t_target);
+
+ if (addr_p)
+ *addr_p = addr;
+ if (elf_gnu_ifunc_record_cache (name, addr))
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
+ function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
+ is not NULL) and the function returns 1. It returns 0 otherwise.
+
+ Both the elf_objfile_gnu_ifunc_cache_data hash table and
+ SYMBOL_GOT_PLT_SUFFIX locations are searched by this function. */
+
+static int
+elf_gnu_ifunc_resolve_name (const char *name, CORE_ADDR *addr_p)
+{
+ if (elf_gnu_ifunc_resolve_by_cache (name, addr_p))
+ return 1;
+
+ if (elf_gnu_ifunc_resolve_by_got (name, addr_p))
+ return 1;
+
+ return 0;
+}
+
+/* Call STT_GNU_IFUNC - a function returning addresss of a real function to
+ call. PC is theSTT_GNU_IFUNC resolving function entry. The value returned
+ is the entry point of the resolved STT_GNU_IFUNC target function to call.
+ */
+
+static CORE_ADDR
+elf_gnu_ifunc_resolve_addr (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ const char *name_at_pc;
+ CORE_ADDR start_at_pc, address;
+ struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
+ struct value *function, *address_val;
+
+ /* Try first any non-intrusive methods without an inferior call. */
+
+ if (find_pc_partial_function (pc, &name_at_pc, &start_at_pc, NULL)
+ && start_at_pc == pc)
+ {
+ if (elf_gnu_ifunc_resolve_name (name_at_pc, &address))
+ return address;
+ }
+ else
+ name_at_pc = NULL;
+
+ function = allocate_value (func_func_type);
+ set_value_address (function, pc);
+
+ /* STT_GNU_IFUNC resolver functions have no parameters. FUNCTION is the
+ function entry address. ADDRESS may be a function descriptor. */
+
+ address_val = call_function_by_hand (function, 0, NULL);
+ address = value_as_address (address_val);
+ address = gdbarch_convert_from_func_ptr_addr (gdbarch, address,
+ ¤t_target);
+
+ if (name_at_pc)
+ elf_gnu_ifunc_record_cache (name_at_pc, address);
+
+ return address;
+}
+
+/* Handle inferior hit of bp_gnu_ifunc_resolver, see its definition. */
+
+static void
+elf_gnu_ifunc_resolver_stop (struct breakpoint *b)
+{
+ struct breakpoint *b_return;
+ struct frame_info *prev_frame = get_prev_frame (get_current_frame ());
+ struct frame_id prev_frame_id = get_stack_frame_id (prev_frame);
+ CORE_ADDR prev_pc = get_frame_pc (prev_frame);
+ int thread_id = pid_to_thread_id (inferior_ptid);
+
+ gdb_assert (b->type == bp_gnu_ifunc_resolver);
+
+ for (b_return = b->related_breakpoint; b_return != b;
+ b_return = b_return->related_breakpoint)
+ {
+ gdb_assert (b_return->type == bp_gnu_ifunc_resolver_return);
+ gdb_assert (b_return->loc != NULL && b_return->loc->next == NULL);
+ gdb_assert (frame_id_p (b_return->frame_id));
+
+ if (b_return->thread == thread_id
+ && b_return->loc->requested_address == prev_pc
+ && frame_id_eq (b_return->frame_id, prev_frame_id))
+ break;
+ }
+
+ if (b_return == b)
+ {
+ struct symtab_and_line sal;
+
+ /* No need to call find_pc_line for symbols resolving as this is only
+ a helper breakpointer never shown to the user. */
+
+ init_sal (&sal);
+ sal.pspace = current_inferior ()->pspace;
+ sal.pc = prev_pc;
+ sal.section = find_pc_overlay (sal.pc);
+ sal.explicit_pc = 1;
+ b_return = set_momentary_breakpoint (get_frame_arch (prev_frame), sal,
+ prev_frame_id,
+ bp_gnu_ifunc_resolver_return);
+
+ /* set_momentary_breakpoint invalidates PREV_FRAME. */
+ prev_frame = NULL;
+
+ /* Add new b_return to the ring list b->related_breakpoint. */
+ gdb_assert (b_return->related_breakpoint == b_return);
+ b_return->related_breakpoint = b->related_breakpoint;
+ b->related_breakpoint = b_return;
+ }
+}
+
+/* Handle inferior hit of bp_gnu_ifunc_resolver_return, see its definition. */
+
+static void
+elf_gnu_ifunc_resolver_return_stop (struct breakpoint *b)
+{
+ struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
+ struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
+ struct type *value_type = TYPE_TARGET_TYPE (func_func_type);
+ struct regcache *regcache = get_thread_regcache (inferior_ptid);
+ struct value *value;
+ CORE_ADDR resolved_address, resolved_pc;
+ struct symtab_and_line sal;
+ struct symtabs_and_lines sals, sals_end;
+
+ gdb_assert (b->type == bp_gnu_ifunc_resolver_return);
+
+ value = allocate_value (value_type);
+ gdbarch_return_value (gdbarch, func_func_type, value_type, regcache,
+ value_contents_raw (value), NULL);
+ resolved_address = value_as_address (value);
+ resolved_pc = gdbarch_convert_from_func_ptr_addr (gdbarch,
+ resolved_address,
+ ¤t_target);
+
+ while (b->related_breakpoint != b)
+ {
+ struct breakpoint *b_next = b->related_breakpoint;
+
+ switch (b->type)
+ {
+ case bp_gnu_ifunc_resolver:
+ break;
+ case bp_gnu_ifunc_resolver_return:
+ delete_breakpoint (b);
+ break;
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("handle_inferior_event: Invalid "
+ "gnu-indirect-function breakpoint type %d"),
+ (int) b->type);
+ }
+ b = b_next;
+ }
+ gdb_assert (b->type == bp_gnu_ifunc_resolver);
+
+ gdb_assert (current_program_space == b->pspace || b->pspace == NULL);
+ elf_gnu_ifunc_record_cache (b->addr_string, resolved_pc);
+
+ sal = find_pc_line (resolved_pc, 0);
+ sals.nelts = 1;
+ sals.sals = &sal;
+ sals_end.nelts = 0;
+
+ b->type = bp_breakpoint;
+ update_breakpoint_locations (b, sals, sals_end);
+}
+
+struct build_id
+ {
+ size_t size;
+ gdb_byte data[1];
+ };
+
+/* Locate NT_GNU_BUILD_ID from ABFD and return its content. */
+
+static struct build_id *
+build_id_bfd_get (bfd *abfd)
+{
+ struct build_id *retval;
+
+ if (!bfd_check_format (abfd, bfd_object)
+ || bfd_get_flavour (abfd) != bfd_target_elf_flavour
+ || elf_tdata (abfd)->build_id == NULL)
+ return NULL;
+
+ retval = xmalloc (sizeof *retval - 1 + elf_tdata (abfd)->build_id_size);
+ retval->size = elf_tdata (abfd)->build_id_size;
+ memcpy (retval->data, elf_tdata (abfd)->build_id, retval->size);
+
+ return retval;
+}
+
+/* Return if FILENAME has NT_GNU_BUILD_ID matching the CHECK value. */
+
+static int
+build_id_verify (const char *filename, struct build_id *check)
+{
+ bfd *abfd;
+ struct build_id *found = NULL;
+ int retval = 0;
+
+ /* We expect to be silent on the non-existing files. */
+ abfd = bfd_open_maybe_remote (filename);
+ if (abfd == NULL)
+ return 0;
+
+ found = build_id_bfd_get (abfd);
+
+ if (found == NULL)
+ warning (_("File \"%s\" has no build-id, file skipped"), filename);
+ else if (found->size != check->size
+ || memcmp (found->data, check->data, found->size) != 0)
+ warning (_("File \"%s\" has a different build-id, file skipped"),
+ filename);
+ else
+ retval = 1;
+
+ gdb_bfd_close_or_warn (abfd);
+
+ xfree (found);
+
+ return retval;
+}
+
+static char *
+build_id_to_debug_filename (struct build_id *build_id)
+{
+ char *link, *debugdir, *retval = NULL;
+ VEC (char_ptr) *debugdir_vec;
+ struct cleanup *back_to;
+ int ix;
+
+ /* DEBUG_FILE_DIRECTORY/.build-id/ab/cdef */
+ link = alloca (strlen (debug_file_directory) + (sizeof "/.build-id/" - 1) + 1
+ + 2 * build_id->size + (sizeof ".debug" - 1) + 1);
+
+ /* Keep backward compatibility so that DEBUG_FILE_DIRECTORY being "" will
+ cause "/.build-id/..." lookups. */
+
+ debugdir_vec = dirnames_to_char_ptr_vec (debug_file_directory);
+ back_to = make_cleanup_free_char_ptr_vec (debugdir_vec);
+
+ for (ix = 0; VEC_iterate (char_ptr, debugdir_vec, ix, debugdir); ++ix)
+ {
+ size_t debugdir_len = strlen (debugdir);
+ gdb_byte *data = build_id->data;
+ size_t size = build_id->size;
+ char *s;
+
+ memcpy (link, debugdir, debugdir_len);
+ s = &link[debugdir_len];
+ s += sprintf (s, "/.build-id/");
+ if (size > 0)
+ {
+ size--;
+ s += sprintf (s, "%02x", (unsigned) *data++);
+ }
+ if (size > 0)
+ *s++ = '/';
+ while (size-- > 0)
+ s += sprintf (s, "%02x", (unsigned) *data++);
+ strcpy (s, ".debug");
+
+ /* lrealpath() is expensive even for the usually non-existent files. */
+ if (access (link, F_OK) == 0)
+ retval = lrealpath (link);
+
+ if (retval != NULL && !build_id_verify (retval, build_id))
+ {
+ xfree (retval);
+ retval = NULL;
+ }
+
+ if (retval != NULL)
+ break;
+ }
+
+ do_cleanups (back_to);
+ return retval;
+}
+
+static char *
+find_separate_debug_file_by_buildid (struct objfile *objfile)
+{
+ struct build_id *build_id;
+
+ build_id = build_id_bfd_get (objfile->obfd);
+ if (build_id != NULL)
+ {
+ char *build_id_name;
+
+ build_id_name = build_id_to_debug_filename (build_id);
+ xfree (build_id);
+ /* Prevent looping on a stripped .debug file. */
+ if (build_id_name != NULL
+ && filename_cmp (build_id_name, objfile->name) == 0)
+ {
+ warning (_("\"%s\": separate debug info file has no debug info"),
+ build_id_name);
+ xfree (build_id_name);
+ }
+ else if (build_id_name != NULL)
+ return build_id_name;
+ }
+ return NULL;
+}
+
/* Scan and build partial symbols for a symbol file.
- We have been initialized by a call to elf_symfile_init, which
+ We have been initialized by a call to elf_symfile_init, which
currently does nothing.
SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
in each section. We simplify it down to a single offset for all
symbols. FIXME.
- MAINLINE is true if we are reading the main symbol
- table (as opposed to a shared lib or dynamically loaded file).
-
This function only does the minimum work necessary for letting the
user "name" things symbolically; it does not read the entire symtab.
Instead, it reads the external and static symbols and puts them in partial
We look for sections with specific names, to tell us what debug
format to look for: FIXME!!!
- dwarf_build_psymtabs() builds psymtabs for DWARF symbols;
elfstab_build_psymtabs() handles STABS symbols;
mdebug_build_psymtabs() handles ECOFF debugging information.
capability even for files compiled without -g. */
static void
-elf_symfile_read (struct objfile *objfile, int mainline)
+elf_symfile_read (struct objfile *objfile, int symfile_flags)
{
- bfd *abfd = objfile->obfd;
+ bfd *synth_abfd, *abfd = objfile->obfd;
struct elfinfo ei;
struct cleanup *back_to;
- CORE_ADDR offset;
+ long symcount = 0, dynsymcount = 0, synthcount, storage_needed;
+ asymbol **symbol_table = NULL, **dyn_symbol_table = NULL;
+ asymbol *synthsyms;
init_minimal_symbol_collection ();
back_to = make_cleanup_discard_minimal_symbols ();
memset ((char *) &ei, 0, sizeof (ei));
- /* Allocate struct to keep track of the symfile */
- objfile->sym_stab_info = (struct dbx_symfile_info *)
+ /* Allocate struct to keep track of the symfile. */
+ objfile->deprecated_sym_stab_info = (struct dbx_symfile_info *)
xmalloc (sizeof (struct dbx_symfile_info));
- memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info));
+ memset ((char *) objfile->deprecated_sym_stab_info,
+ 0, sizeof (struct dbx_symfile_info));
make_cleanup (free_elfinfo, (void *) objfile);
- /* Process the normal ELF symbol table first. This may write some
- chain of info into the dbx_symfile_info in objfile->sym_stab_info,
- which can later be used by elfstab_offset_sections. */
+ /* Process the normal ELF symbol table first. This may write some
+ chain of info into the dbx_symfile_info in
+ objfile->deprecated_sym_stab_info, which can later be used by
+ elfstab_offset_sections. */
+
+ storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
+ if (storage_needed < 0)
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
+ bfd_errmsg (bfd_get_error ()));
- elf_symtab_read (objfile, 0);
+ if (storage_needed > 0)
+ {
+ symbol_table = (asymbol **) xmalloc (storage_needed);
+ make_cleanup (xfree, symbol_table);
+ symcount = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
+
+ if (symcount < 0)
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
+ bfd_errmsg (bfd_get_error ()));
+
+ elf_symtab_read (objfile, ST_REGULAR, symcount, symbol_table, 0);
+ }
/* Add the dynamic symbols. */
- elf_symtab_read (objfile, 1);
+ storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd);
+
+ if (storage_needed > 0)
+ {
+ /* Memory gets permanently referenced from ABFD after
+ bfd_get_synthetic_symtab so it must not get freed before ABFD gets.
+ It happens only in the case when elf_slurp_reloc_table sees
+ asection->relocation NULL. Determining which section is asection is
+ done by _bfd_elf_get_synthetic_symtab which is all a bfd
+ implementation detail, though. */
+
+ dyn_symbol_table = bfd_alloc (abfd, storage_needed);
+ dynsymcount = bfd_canonicalize_dynamic_symtab (objfile->obfd,
+ dyn_symbol_table);
+
+ if (dynsymcount < 0)
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
+ bfd_errmsg (bfd_get_error ()));
+
+ elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table, 0);
+
+ elf_rel_plt_read (objfile, dyn_symbol_table);
+ }
+
+ /* Contrary to binutils --strip-debug/--only-keep-debug the strip command from
+ elfutils (eu-strip) moves even the .symtab section into the .debug file.
+
+ bfd_get_synthetic_symtab on ppc64 for each function descriptor ELF symbol
+ 'name' creates a new BSF_SYNTHETIC ELF symbol '.name' with its code
+ address. But with eu-strip files bfd_get_synthetic_symtab would fail to
+ read the code address from .opd while it reads the .symtab section from
+ a separate debug info file as the .opd section is SHT_NOBITS there.
+
+ With SYNTH_ABFD the .opd section will be read from the original
+ backlinked binary where it is valid. */
+
+ if (objfile->separate_debug_objfile_backlink)
+ synth_abfd = objfile->separate_debug_objfile_backlink->obfd;
+ else
+ synth_abfd = abfd;
+
+ /* Add synthetic symbols - for instance, names for any PLT entries. */
+
+ synthcount = bfd_get_synthetic_symtab (synth_abfd, symcount, symbol_table,
+ dynsymcount, dyn_symbol_table,
+ &synthsyms);
+ if (synthcount > 0)
+ {
+ asymbol **synth_symbol_table;
+ long i;
+
+ make_cleanup (xfree, synthsyms);
+ synth_symbol_table = xmalloc (sizeof (asymbol *) * synthcount);
+ for (i = 0; i < synthcount; i++)
+ synth_symbol_table[i] = synthsyms + i;
+ make_cleanup (xfree, synth_symbol_table);
+ elf_symtab_read (objfile, ST_SYNTHETIC, synthcount,
+ synth_symbol_table, 1);
+ }
/* Install any minimal symbols that have been collected as the current
minimal symbols for this objfile. The debug readers below this point
do_cleanups (back_to);
/* Now process debugging information, which is contained in
- special ELF sections. */
-
- /* If we are reinitializing, or if we have never loaded syms yet,
- set table to empty. MAINLINE is cleared so that *_read_psymtab
- functions do not all also re-initialize the psymbol table. */
- if (mainline)
- {
- init_psymbol_list (objfile, 0);
- mainline = 0;
- }
+ special ELF sections. */
- /* We first have to find them... */
+ /* We first have to find them... */
bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei);
/* ELF debugging information is inserted into the psymtab in the
and .debug_info (DWARF2) sections then .mdebug is inserted first
(searched last) and DWARF2 is inserted last (searched first). If
we don't do this then the XCOFF info is found first - for code in
- an included file XCOFF info is useless. */
+ an included file XCOFF info is useless. */
if (ei.mdebugsect)
{
/* FIXME should probably warn about a stab section without a stabstr. */
if (str_sect)
elfstab_build_psymtabs (objfile,
- mainline,
ei.stabsect,
str_sect->filepos,
bfd_section_size (abfd, str_sect));
}
- if (dwarf2_has_info (objfile))
+
+ if (dwarf2_has_info (objfile, NULL))
{
- /* DWARF 2 sections */
- dwarf2_build_psymtabs (objfile, mainline);
+ /* elf_sym_fns_gdb_index cannot handle simultaneous non-DWARF debug
+ information present in OBJFILE. If there is such debug info present
+ never use .gdb_index. */
+
+ if (!objfile_has_partial_symbols (objfile)
+ && dwarf2_initialize_objfile (objfile))
+ objfile->sf = &elf_sym_fns_gdb_index;
+ else
+ {
+ /* It is ok to do this even if the stabs reader made some
+ partial symbols, because OBJF_PSYMTABS_READ has not been
+ set, and so our lazy reader function will still be called
+ when needed. */
+ objfile->sf = &elf_sym_fns_lazy_psyms;
+ }
}
- else if (ei.dboffset && ei.lnoffset)
+ /* If the file has its own symbol tables it has no separate debug
+ info. `.dynsym'/`.symtab' go to MSYMBOLS, `.debug_info' goes to
+ SYMTABS/PSYMTABS. `.gnu_debuglink' may no longer be present with
+ `.note.gnu.build-id'. */
+ else if (!objfile_has_partial_symbols (objfile))
{
- /* DWARF sections */
- dwarf_build_psymtabs (objfile,
- mainline,
- ei.dboffset, ei.dbsize,
- ei.lnoffset, ei.lnsize);
+ char *debugfile;
+
+ debugfile = find_separate_debug_file_by_buildid (objfile);
+
+ if (debugfile == NULL)
+ debugfile = find_separate_debug_file_by_debuglink (objfile);
+
+ if (debugfile)
+ {
+ bfd *abfd = symfile_bfd_open (debugfile);
+
+ symbol_file_add_separate (abfd, symfile_flags, objfile);
+ xfree (debugfile);
+ }
}
+}
- /* FIXME: kettenis/20030504: This still needs to be integrated with
- dwarf2read.c in a better way. */
- dwarf2_build_frame_info (objfile);
+/* Callback to lazily read psymtabs. */
+
+static void
+read_psyms (struct objfile *objfile)
+{
+ if (dwarf2_has_info (objfile, NULL))
+ dwarf2_build_psymtabs (objfile);
}
-/* This cleans up the objfile's sym_stab_info pointer, and the chain of
- stab_section_info's, that might be dangling from it. */
+/* This cleans up the objfile's deprecated_sym_stab_info pointer, and
+ the chain of stab_section_info's, that might be dangling from
+ it. */
static void
free_elfinfo (void *objp)
{
struct objfile *objfile = (struct objfile *) objp;
- struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info;
+ struct dbx_symfile_info *dbxinfo = objfile->deprecated_sym_stab_info;
struct stab_section_info *ssi, *nssi;
ssi = dbxinfo->stab_section_info;
file is specified (not just adding some symbols from another file, e.g. a
shared library).
- We reinitialize buildsym, since we may be reading stabs from an ELF file. */
+ We reinitialize buildsym, since we may be reading stabs from an ELF
+ file. */
static void
elf_new_init (struct objfile *ignore)
/* Perform any local cleanups required when we are done with a particular
objfile. I.E, we are in the process of discarding all symbol information
for an objfile, freeing up all memory held for it, and unlinking the
- objfile struct from the global list of known objfiles. */
+ objfile struct from the global list of known objfiles. */
static void
elf_symfile_finish (struct objfile *objfile)
{
- if (objfile->sym_stab_info != NULL)
+ if (objfile->deprecated_sym_stab_info != NULL)
{
- xfree (objfile->sym_stab_info);
+ xfree (objfile->deprecated_sym_stab_info);
}
+
+ dwarf2_free_objfile (objfile);
}
/* ELF specific initialization routine for reading symbols.
a pointer to "private data" which we can fill with goodies.
For now at least, we have nothing in particular to do, so this function is
- just a stub. */
+ just a stub. */
static void
elf_symfile_init (struct objfile *objfile)
void
elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst)
{
- char *filename = pst->filename;
- struct dbx_symfile_info *dbx = objfile->sym_stab_info;
+ const char *filename = pst->filename;
+ struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info;
struct stab_section_info *maybe = dbx->stab_section_info;
struct stab_section_info *questionable = 0;
int i;
- char *p;
/* The ELF symbol info doesn't include path names, so strip the path
(if any) from the psymtab filename. */
- while (0 != (p = strchr (filename, '/')))
- filename = p + 1;
+ filename = lbasename (filename);
/* FIXME: This linear search could speed up significantly
if it was chained in the right order to match how we search it,
- and if we unchained when we found a match. */
+ and if we unchained when we found a match. */
for (; maybe; maybe = maybe->next)
{
if (filename[0] == maybe->filename[0]
- && strcmp (filename, maybe->filename) == 0)
+ && filename_cmp (filename, maybe->filename) == 0)
{
/* We found a match. But there might be several source files
(from different directories) with the same name. */
if (maybe == 0 && questionable != 0)
{
complaint (&symfile_complaints,
- "elf/stab section information questionable for %s", filename);
+ _("elf/stab section information questionable for %s"),
+ filename);
maybe = questionable;
}
/* Found it! Allocate a new psymtab struct, and fill it in. */
maybe->found++;
pst->section_offsets = (struct section_offsets *)
- obstack_alloc (&objfile->objfile_obstack,
+ obstack_alloc (&objfile->objfile_obstack,
SIZEOF_N_SECTION_OFFSETS (objfile->num_sections));
for (i = 0; i < maybe->num_sections; i++)
(pst->section_offsets)->offsets[i] = maybe->sections[i];
/* We were unable to find any offsets for this file. Complain. */
if (dbx->stab_section_info) /* If there *is* any info, */
complaint (&symfile_complaints,
- "elf/stab section information missing for %s", filename);
+ _("elf/stab section information missing for %s"), filename);
+}
+
+/* Implementation of `sym_get_probes', as documented in symfile.h. */
+
+static VEC (probe_p) *
+elf_get_probes (struct objfile *objfile)
+{
+ VEC (probe_p) *probes_per_objfile;
+
+ /* Have we parsed this objfile's probes already? */
+ probes_per_objfile = objfile_data (objfile, probe_key);
+
+ if (!probes_per_objfile)
+ {
+ int ix;
+ const struct probe_ops *probe_ops;
+
+ /* Here we try to gather information about all types of probes from the
+ objfile. */
+ for (ix = 0; VEC_iterate (probe_ops_cp, all_probe_ops, ix, probe_ops);
+ ix++)
+ probe_ops->get_probes (&probes_per_objfile, objfile);
+
+ if (probes_per_objfile == NULL)
+ {
+ VEC_reserve (probe_p, probes_per_objfile, 1);
+ gdb_assert (probes_per_objfile != NULL);
+ }
+
+ set_objfile_data (objfile, probe_key, probes_per_objfile);
+ }
+
+ return probes_per_objfile;
+}
+
+/* Implementation of `sym_get_probe_argument_count', as documented in
+ symfile.h. */
+
+static unsigned
+elf_get_probe_argument_count (struct objfile *objfile,
+ struct probe *probe)
+{
+ return probe->pops->get_probe_argument_count (probe, objfile);
+}
+
+/* Implementation of `sym_evaluate_probe_argument', as documented in
+ symfile.h. */
+
+static struct value *
+elf_evaluate_probe_argument (struct objfile *objfile,
+ struct probe *probe,
+ unsigned n)
+{
+ return probe->pops->evaluate_probe_argument (probe, objfile, n);
+}
+
+/* Implementation of `sym_compile_to_ax', as documented in symfile.h. */
+
+static void
+elf_compile_to_ax (struct objfile *objfile,
+ struct probe *probe,
+ struct agent_expr *expr,
+ struct axs_value *value,
+ unsigned n)
+{
+ probe->pops->compile_to_ax (probe, objfile, expr, value, n);
+}
+
+/* Implementation of `sym_relocate_probe', as documented in symfile.h. */
+
+static void
+elf_symfile_relocate_probe (struct objfile *objfile,
+ struct section_offsets *new_offsets,
+ struct section_offsets *delta)
+{
+ int ix;
+ VEC (probe_p) *probes = objfile_data (objfile, probe_key);
+ struct probe *probe;
+
+ for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++)
+ probe->pops->relocate (probe, ANOFFSET (delta, SECT_OFF_TEXT (objfile)));
}
+
+/* Helper function used to free the space allocated for storing SystemTap
+ probe information. */
+
+static void
+probe_key_free (struct objfile *objfile, void *d)
+{
+ int ix;
+ VEC (probe_p) *probes = d;
+ struct probe *probe;
+
+ for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++)
+ probe->pops->destroy (probe);
+
+ VEC_free (probe_p, probes);
+}
+
\f
+
+/* Implementation `sym_probe_fns', as documented in symfile.h. */
+
+static const struct sym_probe_fns elf_probe_fns =
+{
+ elf_get_probes, /* sym_get_probes */
+ elf_get_probe_argument_count, /* sym_get_probe_argument_count */
+ elf_evaluate_probe_argument, /* sym_evaluate_probe_argument */
+ elf_compile_to_ax, /* sym_compile_to_ax */
+ elf_symfile_relocate_probe, /* sym_relocate_probe */
+};
+
/* Register that we are able to handle ELF object file formats. */
-static struct sym_fns elf_sym_fns =
+static const struct sym_fns elf_sym_fns =
{
bfd_target_elf_flavour,
- elf_new_init, /* sym_new_init: init anything gbl to entire symtab */
- elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */
- elf_symfile_read, /* sym_read: read a symbol file into symtab */
- elf_symfile_finish, /* sym_finish: finished with file, cleanup */
- default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */
- NULL /* next: pointer to next struct sym_fns */
+ elf_new_init, /* init anything gbl to entire symtab */
+ elf_symfile_init, /* read initial info, setup for sym_read() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ NULL, /* sym_read_psymbols */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocation */
+ elf_symfile_segments, /* Get segment information from a file. */
+ NULL,
+ default_symfile_relocate, /* Relocate a debug section. */
+ &elf_probe_fns, /* sym_probe_fns */
+ &psym_functions
+};
+
+/* The same as elf_sym_fns, but not registered and lazily reads
+ psymbols. */
+
+static const struct sym_fns elf_sym_fns_lazy_psyms =
+{
+ bfd_target_elf_flavour,
+ elf_new_init, /* init anything gbl to entire symtab */
+ elf_symfile_init, /* read initial info, setup for sym_read() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ read_psyms, /* sym_read_psymbols */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocation */
+ elf_symfile_segments, /* Get segment information from a file. */
+ NULL,
+ default_symfile_relocate, /* Relocate a debug section. */
+ &elf_probe_fns, /* sym_probe_fns */
+ &psym_functions
+};
+
+/* The same as elf_sym_fns, but not registered and uses the
+ DWARF-specific GNU index rather than psymtab. */
+static const struct sym_fns elf_sym_fns_gdb_index =
+{
+ bfd_target_elf_flavour,
+ elf_new_init, /* init anything gbl to entire symab */
+ elf_symfile_init, /* read initial info, setup for sym_red() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ NULL, /* sym_read_psymbols */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocatin */
+ elf_symfile_segments, /* Get segment information from a file. */
+ NULL,
+ default_symfile_relocate, /* Relocate a debug section. */
+ &elf_probe_fns, /* sym_probe_fns */
+ &dwarf2_gdb_index_functions
+};
+
+/* STT_GNU_IFUNC resolver vector to be installed to gnu_ifunc_fns_p. */
+
+static const struct gnu_ifunc_fns elf_gnu_ifunc_fns =
+{
+ elf_gnu_ifunc_resolve_addr,
+ elf_gnu_ifunc_resolve_name,
+ elf_gnu_ifunc_resolver_stop,
+ elf_gnu_ifunc_resolver_return_stop
};
void
_initialize_elfread (void)
{
+ probe_key = register_objfile_data_with_cleanup (NULL, probe_key_free);
add_symtab_fns (&elf_sym_fns);
+
+ elf_objfile_gnu_ifunc_cache_data = register_objfile_data ();
+ gnu_ifunc_fns_p = &elf_gnu_ifunc_fns;
}
projects / deliverable / binutils-gdb.git / blobdiff